Socket for lamp holder



April 5, 1966 E. G. GODDARD ETAL 3,245,025

SOCKET FOR LAMP HOLDER Filed Nov. 4, 1963 2 Sheets-Sheet 1 FI El April 5, 1966 E. G. GQDDARD ETAL 3,245,025

SOCKET FOR LAMP HOLDER 2 Sheets-Sheet l Filed Nov. 4, 1965 FIC-5-5 6'. kajvlrza 72 1W@ u,

United States Patent() 3,245,025 SOCKET FOR LAMP HOLDER Edwin George Goddard, 125 E. Maple, Lombard, Ill., and Walter C. Chapman, 841 S. Bristol Lane, Arlington Heights, Ill.

Filed Nov. 4, 1963, Ser. No. 321,077 4 Claims. (Cl. 339-32) holders is generally provided with two or more sockets so that two -or more lamps can -be supported. The socket at at least one end of a lamp is resiliently mounted so that the lamp can be inserted or removed, the spacing between the two lamp holders being xed since they are mounted on a iixture channel or the like.

It is an object of our invention to provide a lamp holder construction which permits the use of a much thinner lamp holder casing than has heretofore been used, thus improving the appearance of the xture, and also resulting in a saving of material.

According to this aspect of our invention, the resiliently mounted socket is arranged so that it normally projects forwardly from the front surface of the lamp holder, and is adapted to be displaced rearwardly by the insertion of a lamp. Thus, it is possible to provide a lamp holder casing, the thickness of which is substantially the same as the length'of the resiliently mounted socket body, and the overall length of the resiliently mounted socket body need fbe only from one and one-half to two times the length of the lamp pin.

An object of our invention is to provide ya dual purpose socket which can accommodate either single pin lamps or two-pin lamps, with the result that the lamp holder can be used in any -one of several types of fluorescent lamp circuits, such as a rapid start circuit, an instant start circuit, a lead-lag circuit, or a sequence start circuit.

The lamps for these various circuits are standardized; the two-pin lamp is provided with two pins, each of a diameter of one-sixteenth of an inch, spaced from each other on one-half inch centers. The single pin lamp has a pin, the diameter of which is substantially tive-sixteenths of an inch. The two-pin lamp requires a separate electrical contact or resilient contact member for each pin, and it is customary practice to provide two separate contacts fora single pin lamp.

According to our invention, We arrange the resilient contacts in the socket recess in such a manner that the same contacts cooperate either with the two-pin arrangement or with the one-pin arrangement, and the socket recess is so shaped as to accommodate either pin arrangement.

Other objects, features and advantages will become apparent as the description proceeds.

With reference now to the drawings in which like reference numerals designate like parts:

FIG. 1 shows a side elevation of a pair of lamp holders embodying our invention, with the lamps in place;

FIG. 2 is a plan view of FIG, 1, with parts of the casings Abroken away;

FIG. 3 is an elevation of a lamp holder taken along line 3-3 of FIG. 1;

FIG. 4 is a vertical section taken along line 4-4 of FIG. 2;

FIG. 5 is a section taken substantially along line 5 5 of FIG. 4 showing the socket construction and a two-pin lamp;

FIG. 6 is a plan section taken along line 6-.6 of FIG. 5;

FIG. 7 is a detailed perspective view of one of the contact members;

FIG. Sis an elevation showing a single pin lamp; and FIG. 9 is a fragmentary view-similar to FIG. 5, show- 1ng a modification.

' FIG. 1 shows two lamp holders 10 mounted on a suitable support structure such as a `xture channel 11. Flutlige'scent lamps 12 are supported by the lamp holders Each lamp holder, as shown in FIGS. 3, 4 and 5 comprises a casing in` the form of a U-shaped sheet metal member 13 having a removable cover 14, the cover provrding three of the four edge walls ofthe casing and having ilanges 15 which overlap the edges vof the ycasing 13. The U-shaped casing member 13 provides la front wall 16 having two D-shaped openings 17 and 18 formed therein. A xed socket 20 is mounted in opening 17 and a slidable spring mounted socket Z1 is received in opening 18.

The socket 20 as shown in FIGS. 5 and 6 is preferably formed of glazed porcelain and comprises a body 22 and a front llange 23. An annular groove is formed in the cylindrical surface of the body 22 to receive a spring clip 24. The clip is spaced from the rear surface of the flange by a distance which approximates the thickness of 'thev front wall 16. The cross section of the body 22 matches the D-shape of the `opening 17 so thaty the socket 20 is nonrotatably mounted in the opening. The clip 24 is provided with radially extending tails 25 (FIG. 4) and with a peripherally offset portion 26` whichincrease the bearing surface between the clip and the rear surface of the front wall 16. The clip is resilient so that it can easily be removed Aand replaced, thus providing a convenient device for removably securing the socket 20 within its opening 17.

The body 22 of the socket is provided with an opening or recess 27 of a special shape which extends inwardly from the front surface. Communicating with the recess 27 are two openings 28 which extend through to the rear surface of the body 22, these openings 28 being separated by a core 29.

Resilient electrical contacts 30 are disposed in each of the openings 28. The shape of the contact 30 is shown in FIG. 7. It comprises a front portion 31 having a bent back end 32, a shank 33 and a bent over tail 34. Side projections 35 are disposed between the front portion 31 and the shank 33, and provide shoulders 36 which bear against the front surface of the core 29. The contact 30 is held in place 'by the =bent tail 34 which engages the rear surface of the core 29. Thus, each contact 30 is securely mounted in an opening 28 with the front portion 31 extending forwardly into the recess 27. The stripped end `of a conductor 37 is spot welded to the shank 33. As is apparent from an inspection of FIG. 6, the conductor and contact assembly of FIG. 7 is inserted into the recess 27 and opening 28 from the front of the socket; then the tail 34 of the shank 33 is bent over to secure the parts in place.

The cross sectional configuration of the recess 27 is shown in FIG. 3; it comprises two -rounded ends 40 adapted to receive the pins 41 of a two-pin lamp 12a. The central portion of the recess 27 bulges out at the side to receive the pin 42 of a single pin lamp 12b. Thus, the opening is elongate with generally tapering ends, and the contacts 30 divide t-he recess into an enlarged central portion and two smaller end portions.

In the one case, the small pins 41 engage the bent ends 32 of the front portion 31 to make good electrical contact; in the other case, the diameter of the pin 42 is slightly greater than the spacing between the front portions 31 so as to make good electrical contact between the contacts 30. and the pin 42.

Thus, our improved socket is adapted for use either with a two-pin lamp or a single pin lamp.

However, the arrangement may be reversed, as shown in FIG. 9, the bent end 32 being olset into the smaller end portion of the recess.

The spring mounted socket 21 is substantially the same as the lfixed socket 20 except that the body 22 thereof is somewhat longer, and the clip 24 is spaced from the flange by about three-quarters of an inch, the groove being located adjacent the rear edge of the body 22'. Thus, the socket 21 is slidably mounted within its opening y18, and a coil spring 43 is conned between the rear wall 44 of the casing and the clip 24', In this connection, the `tails 25' and offset portions 26. provide means against which the front end of the spring may bear.

Thus, the .spring mounted socket 21 is normally in an extended position; when a lamp is inserted, it is displaced rearwardly, as shown in FIG. 2. v

In the two-socket lamp holder shown, onlyl one socket is spring mounted whereas the other is xed. However, if preferred both sockets of one lamp holder may be spring mounted and both sockets of the lamp holder may be fixed, this being the more customary arrangement.

Although only prefer-red embodiments of our invention have been s-hown and described herein, it wil-l be understood that various modications and changes may be made therein without departing from the spirit ofv our invention as pointed out in the appended claims.

We claim:

1. A dual purpose socket .for cooperation with either a single pin ora two-pin fluorescent lamp comprising a body member rhaving a recess formed in the front surface thereof, said recessv providing an opening of elongate shape havinggenerally tapering ends, a pair of resilient contacts disposed in said recess Vand dividing same into an enlarged central portion and two smaller end portions.

2. A socket as lclaimed in claim 1 in which the wall of said recess is rounded at said en-d portions.

3. A socket as claimed in vclaim 1 in which the over all length of said opening shape is Ysubstantially veeighths of an inch, and in which the maximum width at said enlarged central portion is substantially live-six- `teenths of an inch.

`4. A socket as claimed in claim 1 in which said resilient contacts have bent over front ends, said bent over ends extending away from said enlarged central portion and into said smaller end portions.

References Cited by the Examiner UNITED `STATES PATENTS 1,336,431 4/ 1920 Halter 339-176 X 2,356,752 8/1944 Deysher 339-176 X 2,432,848 12/ 1947 Workman 339-126 2,43 8,350 3/1948- Reichard 339-32 2,552,111 5/1951 Peterson 339-52 X 2,570,104 10/1951 De Reamer et al. 339-52 X 2,626,976 1/ 1953 Howenstine 339-55 2,644,142 6/ 1953 Danburg 339-32 2,664,553 12/1953 Epstein 339-220 2,715,216 8/1955 Howenstine 339-126 X 2,811,702 10/ 1957 Narozny 339-220 3,111,353 11/1963 Nelson 339-56 X 3,116,098 12/1963 Kulka 339-56 FOREIGN PATENTS 1,046,397 8/ 1953 France. 1,065,532 10/1954 Germany,

PATRICK A. CLIFFORD, Primary Examiner. 

1. A DUAL PURPOSE SOCKET FOR COOPERATION WITH EITHER A SINGLE PIN OR A TWO-PIN FLUORESCENT LAMP COMPRISING A BODY MEMBER HAVING A RECESS FORMED N THE FRONT SURFACE THEREOF, SAID RECESS PROVIDING AN OPENING OF ELONGATE SHAPE HAVING GENERALLY TAPERING ENDS, A PAIR OF RESILIENT CONTACTS DISPOSED IN SAID RECESS AND DIVIDING SAME INTO AN ENLARGED CENTRAL PORTION AND TWO SMALLER END PORTIONS. 